BATTERY CHARGING
Battery charging is the means by which the battery can be restored to its full voltage potential. A battery is fully-charged when:
WARNING:
CAUTION:
Some battery chargers are equipped with polaritysensing circuitry. This circuitry protects the battery charger and the battery from being damaged if they are improperly connected. If the battery state-ofcharge is too low for the polarity-sensing circuitry to detect, the battery charger will not operate. This makes it appear that the battery will not accept charging current. See the instructions provided by the manufacturer of the battery charger for details on how to bypass the polarity-sensing circuitry.
After the battery has been charged to 12.4 volts or greater, perform a load test to determine the battery cranking capacity. Refer to Battery in the index of this service manual for the location of the battery diagnosis and testing procedures for more information on the proper battery load testing procedures. If the battery will endure a load test, return the battery to service. If the battery will not endure a load test, it is faulty and must be replaced.
Clean and inspect the battery hold downs, tray, terminals, posts, and top before completing battery service. Refer to Battery in the index of this service manual for the location of the proper battery cleaning and inspection procedures.
CHARGING A COMPLETELY DISCHARGED BATTERY
The following procedure should be used to recharge a completely discharged battery. Unless this procedure is properly followed, a good battery may be needlessly replaced.
(1) Measure the voltage at the battery posts with a voltmeter, accurate to 1/10 (0.10) volt (Fig. 18). If the reading is below ten volts, the battery charging current will be low. It could take some time before the battery accepts a current greater than a few milliamperes.
Such low current may not be detectable on the ammeters built into many battery chargers.
Fig. 18 Voltmeter Accurate to 1/10 Volt Connected - Typical
(2) Disconnect and isolate the battery negative cable. Connect the battery charger leads. Some battery chargers are equipped with polarity-sensing circuitry.
This circuitry protects the battery charger and the battery from being damaged if they are improperly connected. If the battery state-of-charge is too low for the polarity-sensing circuitry to detect, the battery charger will not operate. This makes it appear that the battery will not accept charging current.
See the instructions provided by the manufacturer of the battery charger for details on how to bypass the polarity-sensing circuitry.
(3) Battery chargers vary in the amount of voltage and current they provide. The amount of time required for a battery to accept measurable charging current at various voltages is shown in the Charge Rate chart. If the charging current is still not measurable at the end of the charging time, the battery is faulty and must be replaced. If the charging current is measurable during the charging time, the battery may be good and the charging should be completed in the normal manner.
CHARGING TIME REQUIRED
The time required to charge a battery will vary, depending upon the following factors:
WARNING: NEVER EXCEED TWENTY AMPERES WHEN CHARGING A COLD (-1 C or 30 F) BATTERY.
THE BATTERY MAY ARC INTERNALLY AND EXPLODE. PERSONAL INJURY AND/OR VEHICLE DAMAGE MAY RESULT.